Win 10 wants to run its bootoptimization program (defrag.exe) as part of its Automatic Maintenance feature. Unfortunately (for me), it seems not to recognize when IFW Backup is active, causing IFW to fail due to cache exhaustion. The system is running 24x7, the backup is automated and has adequate cache as long as Win10 doesn't decide to run defrag on top of IFW Backup. Automatic Maintenance is configured for an interval many hours away from the backup time, yet it still runs bootoptimization randomly in a 24 hour period even though there are "system entering sleep" entries in the System Log for the interval and Automatic Maintenance is supposed to run only when the system is idle.

I prefer not to keep guessing what the disk cache needs to be to accommodate the occasional interference from Automatic Maintenance, yet still get timely defragging done. So far I've tried to control defrag execution by,

1. Manually optimizing the system drive on a weekly basis with Task Manager. This works. 2. Disabling the BootOptimizeFunction in Win Registry. Doesn't work because it disables both Automatic Maintenance and manual defrag /b

Before I try to programmatically disable/enable of BootOptimizeFunction while IFW is running, is there a chance that using VSS instead of PHYLock would eliminate the conflict between IFW and defrag? Either to have Automatic Maintenance recognize the system is busy or to reduce cache requirements? IFW is only backing up C: on a BIOS system.